ASIC just means Application Specific Integrated Circuit. So, a burned FPGA is ASIC. A very bad one, but it is still ASIC. If you want to design a real, clean ASIC then you need to take SHA-256 cores, or design your own, and wire them up manually on a wafer / pcb etc. To do this you would need to have SHA-265 cores in existence at one or more steps in the manufacturing process inside of the country you are outsourcing the manufacturing to. This is where the Export of SHA-256 to China comes into play. If you take an FPGA like spartan and have china make PCB for it and send the whole thing back, you do not need export license. If you decide to send the config file to engineer in china to burn on your FPGA or if you send him SHA-256 cores (physical chips or design schematic) to be assembled in china, you are in violation of export.

EDIT:
By violation of export i meant you are breaking US law assuming you have no export license. It does not mean you cant send it, but you would need to have US government grant you export license (Long and tedious process).